Breakers assistant coach Judd Flavell said the competition had been "fierce" for the spots with the depth of talented young players wanting to be involved at an all-time high.

"All four players have great talent and have the potential to be fulltime Breakers in the future," Flavell said.

"The mix of positions works with our current roster but also as we project a few years down the track and look at key positions in the club's long-term planning.

"Alonzo and Luuk can both fill a variety of guard positions and that versatility is important at this stage of their careers.

"All have spent some time with us in the past, either with me and our coaching team in the academy or in the NBL. They are talented basketballers, but importantly for this club and our values, they are good people and will be the right fit for the culture here."

Flavell said the competitive audition process showed how highly regarded a place in the Breakers pathway is viewed.

"I was amazed - not with the large turnout [over 50 applications], but the way the players gave it their all and played like their lives depended on it during the two-day tryout. It was refreshing to see players diving on the floor, working hard on every little thing to impress and secure a contract."

The Breakers will work closely with each player and their families to nurture their development. That includes helping them prepare for opportunities in the American college system (being looked at by Salt and Witteveen), or a pathway that includes tertiary education and basketball development with the Breakers.

"Players have options now and we are happy to work with them to achieve their dreams," Flavell said.

"This can be through the American college system, but we are also now very much a viable pathway to professional basketball while getting an education."

Salt and Witteveen will take up non-nominated development player contracts, restricting them from travel to away games and any payment so as not to jeopardise possible college opportunities in the United States.

Burton and Bailey will be available to step up should any of the fulltime roster spots become available during the season.

The players will join the club over the next week, with Salt and Witteveen mixing the final year of high school with their basketball commitments.